Hi Padmaja, Well the classic is Design Patterns by Eric Gamma, et. al. I have seen some recent offerings by Sun Press for specialized patterns for J2EE. If you go to amazon or bamm and search on "Java Pattern" you'll probably come up with quite a few. Hope this helps, Michael Morris

Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius - and a lot of courage - to move in the opposite direction. - Ernst F. Schumacher